Scraper chain conveyor channel section

ABSTRACT

A channel section for a scraper-chain conveyor is constituted by a pair of sigma-shaped side walls, and a floor plate welded to the central flanges of the side walls. The sigma-shape of the side walls define V-shaped grooves in the side walls, each of these grooves being defined by a pair of outwardly-divergent inclined wall portions. Each end zone of each side wall is provided with a coupling element for coupling the channel section to an adjacent similar channel section. Each of the coupling elements is welded into a cut-away part formed at the adjacent end zone of the respective inclined wall portions. The coupling elements are provided with recesses for the reception of a connector such as a toggle bolt connector. Each of the side walls is provided with elongate stiffening members welded thereto adjacent to the upper and lower flanges respectively. The coupling elements protrude outwardly beyond their side walls as far as the outer edges of the stiffening members.

BACKGROUND TO THE INVENTION

This invention relates to a channel section for a scraper-chainconveyor.

Known scraper-chain conveyors, which are used primarily in undergroundmine workings, are constituted by a series of channel sections (orpans), which are connected together in an end-to-end relationship. Thechannel sections of one known type of scraper-chain conveyor havesigma-section side walls and a floor plate welded to the centralportions of the side walls. Each of the side walls hasinwardly-extending flanges at the top, the centre, and the base, thecentral flange being connected to the top and base flanges by means of aV-shaped wall section and by respective short vertical wall sections.The V-shaped wall sections define V-shaped grooves in the externalsurfaces of the side walls. The floor plate is welded to the centralflanges of the sigma-shaped side walls.

A variety of devices for connecting the individual channel sections areknown. Such devices normally resist tensile forces which tend to drawthe ends of the channel sections apart; whilst permitting some angularmobility, in all directions, between the channel section ends. Theconnection devices are often subjected to very high forces duringoperation, not only the tensile forces which they are designed toresist, but also buckling forces tending to displace the conveyor endslaterally and/or vertically. Primarily, the lateral forces occur whenthe conveyor is advanced to follow up the mineral winning progress. Thisis usually accomplished by means of rams, which shift individual lengthsof conveyor in a so-called "snaking" movement. The vertical forcesusually occur when a mining machine supported on the conveyor is moved,for example, along the mineral face being won. Where the mine working isuneven, the lateral and vertical forces can increase substantially.Attachments, such as spill plates, and plough guides, are frequentlybolted to the side walls of the channel sections. For this purpose,spill plate holders and guide plate holders are welded into the V-shapedgrooves of the side walls.

One known way of connecting the individual channel sections of ascraper-chain conveyor is to provide interlocking coupling elements onthe adjacent ends of each pair of adjacent channel sections. Each pairof interlocked coupling elements is connected together by means of screwbolts, so that the tensile forces can be transmitted between the channelsection ends. The dimensions of the screw bolts that can be used forsuch connections are restricted by the dimensions of the V-shapedgrooves in the channel section side walls. Unfortunately, thisrestriction on bolt size frequently results in the bolts beinginadequate for the heavy loadings to which they are subjected. (seeDE-OS No. 2 516 082).

It is also known to reinforce the side walls of the channel sections ofa scraper-chain conveyor by welding stiffening members to the shortvertical wall sections adjacent to the top and base flanges of thesigma-shaped side walls. The stiffening members lie flush with the topand base flanges, and also serve as backing members to which attachmentssuch as spill plate holders and machine guides can be bolted. Thestiffening members extend over substantially the entire length of thechannel section side walls. Channel sections of this type are connectedtogether by means of interlocking coupling elements and screw bolts.Here, the coupling elements are welded to the channel section side wallsat the end portions thereof. The coupling elements also constitutestiffening members in these end portions where the longitudinalstiffening members are absent.

It is also known to join the interlocking coupling elements together bymeans of a toggle bolt (or dog-bone) connector. Such connector has anenlarged head at each end of a smooth shank. In this case,laterally-open recesses are provided in the coupling elements forreceiving the connector. The connector is secured in place within therecesses in the coupling elements by means of removable retainingelements, such as C-shaped spring clips. Here again, the size of theconnector is limited by the dimensions of the V-shaped grooves in thechannel section side walls. Consequently, connections of this type maysometimes be inadequate to take up the heavy loadings which can occur.(see DE-OS No. 2 636 527).

The aim of the invention is to provide a scraper-chain conveyor channelsection which does not suffer from the disadvantages of the knownchannel sections.

SUMMARY OF THE INVENTION

The present invention provides a channel section for a scraper-chainconveyor, the channel section comprising a pair of side walls and afloor plate extending between the side walls and connecting the sidewalls together, each of the side walls having a V-shaped grooveextending longitudinally along the exterior surface thereof, each of theV-shaped grooves being defined by a pair of outwardly-divergent inclinedwall portions, each end zone of each side wall being provided with acoupling element for coupling the channel section to an adjacent similarchannel section, wherein each of the coupling elements is housed in acut-away part formed at the adjacent end zone of the respective inclinedwall portions.

Advantageously, each of the side walls has a generally sigma-shapedcross section which defines three vertically-spaced, inwardly-extendingflanges, the central flange being joined to the upper and lower flangesby said inclined wall portions, and by respective short vertical wallsections. Conveniently, the floor plate is welded to the central flangesof the side walls. Preferably, the channel section further compriseselongate stiffening members attached to each of said short vertical wallsections of each of the side walls, the elongate stiffening membersextending along substantially the entire length of the side walls. Eachof the elongate stiffening members may be welded to its short verticalwall section, and each may lie flush with its respective upper or lowerflange.

Preferably, each of the coupling elements protrudes outwardly beyond theprofile of its side wall by approximately the thickness of thestiffening members attached to that side wall. Advantageously, each ofthe coupling elements is welded into its respective cut-away part, andeach of the coupling elements is provided with an outwardly-openrecessed portion for receiving part of a toggle bolt connector.

By welding the coupling elements into the cut-away parts at the ends ofthe side walls, a strong construction results without the upper andlower flanges of the side walls being affected. Moreover, the couplingelements can be larger and stronger than known coupling elements (asthey can protrude out as far as the edges of the stiffening members), sothey can accommodate larger and stronger connectors.

Advantageously, each of the coupling elements is generally V-shaped, theoutwardly-divergent arms of which have a greater thickness than theadjacent outwardly-divergent wall portions of the side walls.Conveniently, each of the recessed portions is contiguous with theV-shaped groove in the associated side wall.

The coupling elements attached to each side wall may be formed withcomplementary end portions. Preferably, one of said end portions isprovided with a projection, and the other of said end portions isprovided with a complementary-shaped recess.

In a preferred embodiment, the stiffening members associated with eachof the side walls are interconnected, at longitudinally-spacedlocations, by transverse members. Conveniently, the transverse membersare welded to the stiffening members, and the transverse members arepositioned at the level of the V-shaped groove in the associated sidewall. Advantageously, each of the transverse members is provided with aslot for receiving the shank of a bolt, and wherein each of thetransverse members is provided, at the rear, with a socket for receivinga bolt head. Preferably, a respective transverse member is positionedadjacent to each coupling element, and wherein the aperture of each ofsaid transverse members is provided with inclined guide surfaces forguiding the head of a bolt into the socket of that transverse member.Each of said transverse members may be formed with an aperture forreceiving a securing element (such as a C-shaped spring clip) for thetoggle bolt connector. Conveniently, each of said transverse members isof one-piece construction, and is welded to its associated couplingelement.

Preferably, the stiffening members are formed with bolt holes, the boltholes being of key-hole shape and being provided with enlargements atthe rear for receiving the heads of bolts.

Advantageously, each of the stiffening members is substantially the samelength as the channel section, and wherein the stiffening members ofeach side wall protrude beyond one end of that side wall and are setback relative to the other end of that side wall.

The invention also provides a scraper-chain conveyor comprising aplurality of channel sections joined together end-to-end, wherein eachof the channel sections is as defined above. Preferably, the channelsections are connected together by means of toggle bolt connectors.

DESCRIPTION OF THE DRAWINGS

The invention will now be described in greater detail, by way ofexample, with reference to the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of one end of a scraper-chainconveyor channel section constructed in accordance with the invention;

FIG. 2 is a side elevation of the channel section end portion shown inFIG. 1;

FIG. 3 is an end view, looking in the direction of the arrow III of FIG.2, of the channel section end portion;

FIG. 4 is a side elevation of the channel section end portion, which isshown connected to a similar channel section end portion;

FIGS. 5 and 6 are each cross-sections taken on the line V--V of FIG. 1,and show how a bolt is introduced to fix a holder to the channelsection;

FIG. 7 is a perspective view of the head of the bolt shown in FIGS. 5and 6; and

FIG. 8 is a transverse cross-section through one side wall of thechannel section, and shows a holder attached thereto.

DESCRIPTION OF PREFERRED EMBODIMENT

Referring to the drawings, FIG. 1 shows one end portion of a channelsection (or pan) 10 of a scraper-chain conveyor. The scraper-chainconveyor is constituted by a plurality of channel sections 10 joinedtogether end-to-end. Each channel section 10 has a floor plate 12 weldedbetween a pair of side walls 11. Each of the side walls 11 is a rolledsteel member having a generally sigma-shaped cross-section. Thus, eachside wall 11 has three inwardly-extending, horizontal flanges, namely atop flange 13, a base flange 14, and a central flange 15. The centralflange 15 of each side wall 11 is joined to its top and base flanges 13and 14 by means of outwardly-divergent walls 16 and 17 and shortvertical walls 16' and 17'. The outwardly-divergent walls 16 and 17 ofeach side wall 11 define a V-shaped groove 18 which extends along theoutside of that side wall. Elongate stiffening members 19 and 20 arewelded to the short vertical walls 16' and 17' of each side wall 11; thestiffening members extending substantially the entire length of thechannel section 10, and lying flush with the top and base flanges 13 and14 respectively.

Each pair of elongate stiffening members 19 and 20 are interconnected,at spaced intervals, by transverse members in the form of shapedbrackets or holders 21. FIG. 1 shows only one of these holders 21,namely that situated adjacent to the illustrated channel section end.The holders 21 are welded to their stiffening members 19 and 20, and arelocated within the associated V-shaped groove 18. The holders 21 enableattachments, such as spill plates and guide members, to be connected tothe side walls 11 of the channel section 10.

Each of the elongate stiffening members 19 and 20 is provided with aseries of longitudinally-spaced, key-hole shaped bolt apertures 22, eachof which is provided with a socket 23 for the reception of a bolt head.Thus, bolts can be introduced into the widened portions of the apertures22, and slid along these apertures until their heads engage within thesockets 23 formed in the rear surfaces of the stiffening members 19 and20. These bolts can be used to assist with the fixing of attachmentssuch as spill plates and guide members.

At the ends of each side wall 11, the channel sections 10 are providedwith reinforced coupling elements 24 and 25 (FIGS. 1 and 2 show one onlyof these coupling elements--namely element 24--and FIG. 4 shows theelements 24 and 25 of two adjacent channel sections). Each of thecoupling elements 24 and 25 is made of wear-resistant material and iswelded to the adjacent end portion of the corresponding channel sectionside wall 11. As best seen in FIG. 4, each of the coupling elements 24is provided with a projection 26 which mates, with an all-roundclearance, with a recess 26' formed in the adjacent coupling element 25.

Each of the coupling elements 24 and 25 is welded into a cut-awayportion 27 formed in the adjacent end zone of the divergent walls 16 and17 (see FIG. 1). The cut-away portions 27 each remove a section of theend zone of the respective side wall 11, apart from the top flange 13,the base flange 14, and the upper and lower parts respectively of thevertical wall sections 16' and 17'. The coupling elements 24 and 25 canthen be introduced into their cut-away portions 27 from the side (asindicated by the arrows shown in FIG. 1). Each of the coupling elements24 and 25 is of a generally V-shaped configuration, havingoutwardly-divergent arms 28 and 29. As best seen by a comparison ofFIGS. 3 and 8, the arms 28 and 29 are considerably thicker than theoutwardly-divergent walls 16 and 17 of the side walls 11. Each couplingelement 24 and 25 is provided with an inwardly-extending curved flange30, which is welded to the floor plate 12.

The coupling elements 24 and 25 are formed with outwardly-open recesses31 and 32 respectively. These recesses 31 and 32 are shaped to receive atoggle bolt (dog-bone) connector 34 (see FIG. 4). The connectors 33 havea central smooth shank 35 of generally triangular cross-section.Enlarged heads 36 and 37 are formed at the two ends of the shank 35 ofeach connector 34. Each head 36 is provided with an axially-extendingfastening member 38, which engages within a complementary recess (seeFIG. 4) formed in the adjacent holder 21, so as to lock the connector 34to the left-hand channel section 10 (as seen in FIG. 4). The other head37 of each connector 34 is provided with shoulders 39 which engagebehind complementary recesses formed in the associated coupling element25. Thus, each of the connectors 34 is prevented from falling laterallyout of its recesses 31 and 32 by means of its fastening member 38 andits shoulders 39. A respective C-shaped spring clip 40 (see FIG. 4) isprovided for preventing each connector 34 from moving axially, the clips40 being inserted into their recesses 32 from the outside. Each clip 40is held in place within a socket formed in the corresponding holder 21.

As best seen from FIG. 3, each of the coupling elements 24,25 protrudesoutwardly with respect to its side wall 11 by a distance X whichcorresponds substantially to the thickness of the stiffening members 19and 20 associated with that side wall. Thus, the external surfaces ofthe coupling elements 24 and 25 lie substantially flush with theexternal surfaces of the corresponding stiffening members 19 and 20.Moreover, as shown best in FIG. 1, each of the recesses 31 is contiguouswith the adjacent V-shaped groove 18. Similarly, the recesses 32 arecontiguous with the V-shaped grooves 18. Accordingly, the recesses 31and 32 each have a comparatively large cross-section, so that they canaccommodate connectors 34 of a correspondingly large cross-section. Inother words, the channel sections 10 can be connected together byconnectors 34 which are larger (and therefore stronger) than knownconnectors. Consequently, the channel section 10 can be connectedtogether in a more reliable manner than was possible with prior artarrangements.

As mentioned above, attachments can be secured to the side walls 11,using threaded bolts, the holders 21, and the stiffening members 19 and20. For example, FIGS. 5, 6 and 8 show the attachment of a guide rail 41(shown in dash-dot lines). The guide rail 41 constitutes a lower guidemember for a plough which is reciprocable along the conveyor. The guiderail 41 is provided with horizontal elongate slots 42, through whichbolts 43 extend to connect the guide rail to the holders 21. Each of thebolts 43 (see FIG. 7) has a stepped head 44, whose width B is greaterthan its height H, and which has a narrower inwardly-stepped portion ofwidth A. Each of the holders has a slot 45 and a socket 46 for receivinga bolt 43.

Each of the holders 21 positioned adjacent to an end of a side wall 11is welded between the corresponding stiffening members 19 and 20 in sucha way that its slot 45 opens out towards the centre of that side wall.Thus, a bolt 43 can be introduced into the slot 45 from the side, andthen slid along so its head 44 lies in the socket 46. To facilitate theintroduction of a bolt 43, each end holder 21 is formed with inclinedguide surfaces 47 and 48, these surfaces being effective to guide thebolt head 44 into the socket 46 (see FIGS. 5 and 6). Thus, as shown inFIG. 5, the bolt 43 is introduced through the slot 42, and into the slot45, in an oblique position. When the head 44 abuts the guide surfaces 47and 48, the bolt 43 is pivoted (as indicated by the arrows in FIG. 5),and rotated about its axis, so that the head 44 moves into the socket 46(see FIG. 6). The bolt 43 then lies perpendicular to the side wall 11,so that the guide rail 41 can be fixed thereto by screwing a nut ontothe threaded end portion of the bolt. Obviously, the guide rail 41 isalso fixed to the side wall 11 by means of nuts and bolts associatedwith the stiffening members 19 and 20.

The stiffening members 19 and 20 are welded to the side wall sections16' and 17' so that they protrude slightly beyond one end of therespective side wall 11, and so that they are set back slightly relativeto the other end (as shown in FIG. 1). Thus, when the channel sections10 are connected together, the protruding stiffening members 19 and 20of one channel section side wall engage within the apertures formed bythe set back stiffening members of the adjacent side wall. This resultsin an improved form of connection.

We claim:
 1. A channel section for a scraper-chain conveyor, the channelsection comprising a pair of side walls and a floor plate extendingbetween the side walls and connecting the side walls together, each ofthe side walls having a generally sigma-shaped cross section defining aV-shaped groove extending longitudinally along the exterior surfacethereof and three vertically-spaced inwardly-extending flanges, thecentral flange being joined to the upper and lower flanges by a pair ofoutwardly-divergent inclined wall portions and by respective shortvertical wall sections, each of the side walls having elongatestiffening members extending substantially the entire length thereof andattached to said short vertical wall sections, each end zone of eachside wall being provided with a coupling element for coupling thechannel section to an adjacent similar channel section, each of thecoupling elements being housed in a cut-away part formed at the adjacentend zone of the respective inclined wall portions and being shaped toprotrude outwardly beyond the profile of its side wall by approximatelythe thickness of the stiffening members attached to that side wall, thestiffening members associated with each of the side walls beinginterconnected at longitudinally spaced intervals adjacent to eachcoupling element, by transverse members which are positioned at thelevel of the V-shaped groove in the associated side wall and which arewelded to the stiffening members, each transverse member being providedwith a slot for receiving the shank of a bolt, with a socket at its rearfor receiving a bolt head, and with an aperture with inclined guidesurfaces for guiding the head of a bolt into said socket.
 2. A channelsection according to claim 1, wherein the floor plate is welded to thecentral flanges of the side walls.
 3. A channel section according toclaim 1, wherein each of the elongate stiffening members is welded toits short vertical wall section.
 4. A channel section according to claim1, wherein each of the stiffening members lies flush with its respectiveupper or lower flange.
 5. A channel section according to claim 1,wherein each of the coupling elements is welded into its respectivecut-away part.
 6. A channel section according to claim 1, wherein eachof the coupling elements is provided with an outwardly-open recessedportion for receiving part of a toggle bolt connector.
 7. A channelsection according to claim 6, wherein each of the coupling elements isgenerally V-shaped, the outwardly-divergent arms of which have a greaterthickness than the adjacent outwardly-divergent wall portions of theside walls.
 8. A channel section according to claim 7, wherein each ofthe recessed portions is contiguous with the V-shaped groove in theassociated side wall.
 9. A channel section according to claim 1, whereinthe coupling elements attached to each side wall are formed withcomplementary end portions.
 10. A channel section according to claim 9,wherein one of said end portions is provided with a projection, and theother of said end portions is provided with a complementary-shapedrecess.
 11. A channel section according to claim 1, wherein each of saidtransverse members is formed with an aperture for receiving a securingelement for a toggle bolt connector.
 12. A channel section according toclaim 1, wherein each of said transverse members is of one-piececonstruction, and is welded to its associated coupling element.
 13. Achannel section according to claim 1, wherein the stiffening members areformed with bolt holes, the bolt holes being of key-hole shape and beingprovided with enlargements at the rear for receiving the heads of bolts.14. A channel section according to claim 1, wherein each of thestiffening members is substantially the same length as the channelsection, and wherein the stiffening members of each side wall protrudebeyond one end of that side wall and are set back relative to the otherend of that side wall.
 15. A scraper-chain conveyor comprising aplurality of channel sections joined together end-to-end, each of thechannel sections comprising a pair of side walls and a floor plateextending between the side walls and connecting the side walls together,each of the side walls having a generally sigma-shaped cross sectiondefining a V-shaped groove extending longitudinally along the exteriorsurface thereof and three vertically-spaced inwardly extending flanges,the central flange being joined to the upper and lower flanges by a pairof outwardly-divergent inclined wall portions and by respective shortvertical wall sections, each of the side walls having elongatestiffening members extending substantially the entire length thereof andattached to said short vertical wall sections, each end zone of eachside wall being provided with a coupling element for coupling thechannel section to an adjacent channel section, each of the couplingelements being housed in a cut-away part formed at the adjacent end zoneof the respective inclined wall portions and being shaped to protrudeoutwardly beyond the profile of its side wall by approximately thethickness of the stiffening members attached to that side wall, thestiffening members associated with each of the side walls beinginterconnected at longitudinally spaced intervals adjacent to eachcoupling element, by transverse members which are positioned at thelevel of the V-shaped groove in the associated side wall and which arewelded to the stiffening members, each transverse member being providedwith a slot for receiving the shank of a bolt, with a socket at its rearfor receiving a bolt head, and with an aperture with inclined guidesurfaces for guiding the head of a bolt into said socket.
 16. Ascraper-chain conveyor according to claim 15, wherein the channelsections are connected together by means of toggle bolt connectors.